How can I make an experiment board for an EyasSAT?

The best way is to make a board in the PC-104 physical format that meets the EyaBus specification.

The required connections are the SPI pins, one of the CS lines dedicated to experiments, and power.

Any microcontroller that talks SPI could be used, Atmel and PIC are the likely candidates. A single purpose IC that talks SPI might also be used.

The document "How to design an experiment" in the Downloads section contains all the details you need to build an experiment board that plugs into the EyasSAT stack.

We strongly recommend one of the switched power pins be used to run the board. 5V and 3.3V are available.

There are also discrete I/O pins from the IHU available to interface to experiment boards. See the hardware manual and the EyaBUS pin diagram for further detail.

Addtionally it is possible to unplug the torque rods and plug in other devices that operate from a PWM 9VDC source.